Wetting and dispersing agents containing a water-soluble lignosulfonic acid salt



Unitfid S ates ate wETfiNG AND, .msraasnsc GENTS CONTAIN- TING A WATER-SOLUBLE LIGNOSULFONIC ACID. SALT James C. Wiedow, Creve Coeur, Mo., assignor to Monsanto Chemical Company, St. LlliS,.M0'., a corporation of Delaware N0 Drawing. Application August 29, 1955 Serial No. 531,281

11 Claims. (c1. 167-42 This invention relates to a wetting and dispersing agent which is adapted forthe preparation of solid powders capable of beingreadily dispersed in water. More specifically, the invention relates to formulations, and particularly biocide formulations, suitable for the preparation of non-foaming permanent dispersions in both hard and soft water.

It is conventional to use wetting agents in treating water-insoluble powders for the purpose of rendering them readily dispersible in Water. Many of the known wetting agents are objectionable in that they are not capable of use in both hard and soft waters. Many of the known dispersing agents foam excessively and are, therefore, not adaptable to many types of application equipment. Many of the known dispersing agents do not provide a permanent suspension, the insoluble powder separating from the suspending medium upon storage or during use. Although all of these properties are recognized as desirable, it is difiicult to achieve all in the same formulation, and a formulation superior with respect to all of the properties is virtually unknown.

This invention, which is based upon the use of a salt of lignosulfonic acid and preferably the sodium salt, requires in addition other wetting and dispersing agents to provide a formulation with a high level of performance with respect to the several desired properties. Sodium lignosulfonate is known to be a dispersing agent which is usable in hard water; however, it does not have value as a wetting agent. Accordingly, it has been found that the use of a condensation product of a rosin acid and ethylene oxide will greatly improve the wetting properties of the sodium lignosulfonate. The combination of these two active components is still not satisfactory, because the powder is not redispersible in water, but it hasbeen found that the addition of an acetylenic glycol will not only render the formulation redispersible, but it further improves the wetting and dispersing properties. It has been found that the proper combination of the various wetting and dispersing agents provides a synergistic effect in the preparation of desirable formulations of a wide variety of insecticides, herbicides, fungicides and other industrial and agricultural formulations. It has been found that even coarse powders, prepared by ordinary grinding methods, for example, in hammermills, will readily form stable suspensions in water containing as high as 1,000 p.p.m. of total hardness.

The new wetting and dispersing agent will contain from thirty (30) to eighty (80) percent by weight of the rosin acid esters made by the condensation of the rosin acid with ethylene oxide. A very useful group of esters are those in which one (1) mole of rosin, rosin acid or tall oil is condensed with from five (5) to twenty (20) moles of ethylene oxide. A preferred class of wetting and dispersing agents are those wherein the rosin acid ester is present to the extent of 40 to 65 percent by weight.

" The new wetting agents also contain soluble salts of lignosulfonic acid, for example, the alkali metal salts and particularly the sodium lignosulfonate. These salts may be present to the extentof 10 R percent by weight and preferably 20 to 30 percent. a

A critical component of the new dispersing agents is the acetylenic glycol having the structural formula in which the R, R, R" and R represent alkyl radicals having up to six (6) carbon atoms. These glycols may be present to the extent of 10 to 35 and preferably from 20 to 30 percent by weight.

A preferred class of the acetylenic glycols are those having the structural formula wherein R and R are alkyl radicals containing three (3) to five (5) carbon atoms. Suitable acetylenio glycols are those prepared by condensing acetylene with aliphatic ketones. For example, the compound of Formula A wherein R, R, R" and RT are all methyl is prepared by condensing two moles of acetone with one of acety- Among the preferred class of acetylenic glycols (Formula B) are those prepared from mixed ketones for example, methyl isopropyl ketone, methyl isobutyl ketone and methyl isoamyl ketone, with acetylene to form a compound such as In the use of the novel wetting and dispersing agents any water-insoluble, finely divided solid substance can be rendered readily and completely dispersible in water for the purpose of preparing non-foaming suspensions in water of any degree of hardness. Suitable dusts for this formulation may be any of the'conventional solid biocidal agents, for example, tetram'ethylthiuram disulfide, DDT (dichlorodiphenyl trichlorethane), lindane (gamma-1,2, 3,4,5,6-hexachlorocyclohexane), dieldrin, aldrin, endrin, isodrin, chlordane, DDYP (2,2-dichlorovinyl dimethyl phosphate), captan (N-[trichloromethylthiol-4-cyclohexene-1,2-dicarboximide), other solid fungicides, insecticides, herbicides and bactericides, and other conventional solid substances used in agricultural and industrial formulations.

, It is sometimes desirable to include in the formulation solid diluents which facilitate the preparation, storage, handling, and use of the wettable powders. Through the use of these substances a product otherwise having the tendency to cake may be rendered permanently freeflowing. The diluents also enable the uniform applica tion of the active ingredient by preventing local excesses of the active ingredient. The solid diluents also tend to make the active component more available over a longer period of time than would otherwise be possible. Suitable diluents include the various natural minerals, for example, clays, such as kaolinite, fullers earth, bentonite, hydrous aluminum silicate and attapulgite, diatomaceous earth or other forms of silica, talc, mica, chalk and pyrophyllite. Other chemically modified natural products are capable of use as diluents, for example, the acid Washed bentonites, the reprecipitated calcium o-phosphates, and the reprecipitated calcium carbonates. Other water-in soluble solid substances either natural, mineral, chemically modified or wholly synthetic substances may also be used.

In the preparation of formulations it has been found that the active component may be present to the extent of 5 to 97 percent, the solid diluent from to 92 percent and the new dispersing and wetting agent to the extent of 3 to 12 percent. In the preferred formulations it has been found that dispersing agents will usually vary between 5 and percent, the active component from to 80 percent and the solid diluents from 15 to 80 percent. It will be apparent to one skilled in the art that the formulations are variable within certain limits and may be adapted by the user in accordance with the specific requirements of the biological toxicant, or other active agent, the particular type of application contemplated, and the conventional practice in the art.

The solid diluent containing formulations may be those wherein the diluent acts as a carrier for liquid active agents such as tetraethyl pyrophosphate, tetraethyl dithiopyrophosphate, parathion (0,0 diethyl O-[p-nitrophenyllphosphorothioate), methylparathion, malathion (diethyl[dimethoxyphosphinothioylthio] succinate), demeton (0,0-diethyl O-[2-{ethylthio}ethyl]phosphorothioate) and other liquid toxicants and other liquid compounds of which readily dispersible wettable powders are desired.

Further details of the practice of this invention will be set forth with respect to the following examples.

Example 1 A finely pulverized DDT was formulated using kaolin as the solid diluent and the dispersing and wetting agent as follows:

Wt. percent Dichlorodiphenyl trichloroethane (DDT) 50.0 Kaolin 43.5 Sodium lignosulfonate 1.5 Product of tall oil (1 mole) and ethylene oxide (11 moles) 3.5 2,4,7,9-tetramethyl-5-decyne-4,7-diol 1.5

This composition was readily dispersed in water containing 1,000 p.p.m. of hardness to form a stable non-foaming suspension. The resulting wettable powder was completely dispersible in both hard and soft waters.

Example 2 Using the procedure described in the previous example the following components were blended.

A readily dispersible pulverulent toxicant was formed which was useful in both hard and soft waters.

4 Example 3 Another excellent biocidal formulation was prepared by blending the following into a solid mixture.

This mixture was mixed with hard water to form stable dispersions of parathion which did not foam during use.

What is claimed is:

1. The wetting and dispersing agent comprising 30 to percent by weight of condensation product of one mole of rosin acid and from 5 to 20 moles of ethylene oxide, from 10 to 35 percent of an acetylenic glycol having the formula wherein R, R, R" and R'" are alkyl radicals having up to six (6) carbon atoms, and from 10 to 35 percent of a Water soluble lignosulfonic acid salt.

2. The wetting and dispersing agent comprising 40 to 65 percent by weight of condensation product of 1 mole of rosin acid and from 5 to 20 moles of ethylene oxide, from 20 to 30 percent of an acetylenic glycol having the formula wherein R and R are alkyl radicals having three (3) to five (5) carbon atoms and from 20 to 30 percent of a water soluble lignosulfonic acid salt.

3. A wettable pulverulent solid comprising 88 to 97 percent by weight of a water -insoluble, finely divided solid and from 3 to 12 percent of the dispersing agent defined by claim 1 4. A wettable pulverulent solid biologically toxic composition comprising up to 92 percent of a solid pulverulent diluent based on the total composition, 5 to 97 percent of a finely divided solid toxicant and from 3 to 12 percent of the wetting and dispersing agent defined by claim 1.

5. A wettable pulverulent solid biologically toxic compound comprising 15 to 80 percent of a Water-insoluble finely divided toxicant, from 15 to 80 percent of a solid diluent and from 5 to 10 percent of the dispersing agent defined by claim 2.

6. A wettable pulverulent solid biologically toxic composition comprising a mixture of a liquid toxicant, sufficient water-insoluble solid pulverulent diluent to absorb the said liquid toxicant and produce a pulverulent mixture, and from 3 to 12 percent (based on the weight of the said toxic composition) of the wetting and dispersing agent defined by claim 1.

7. The composition defined by claim 6 wherein the liquid toxicant is 0,0-diethyl O-(p-nitrophenyDphosphorothiate. I

8. The composition defined by claim 4 wherein the toxicant is dichlorodiphenyl trichlorethane.

9. The composition defined by claim 4 wherein the toxicant is gamma-1,2,3,4,5,6-hexachlorocyclohexane.

10. The composition defined by claim 4 wherein the toxicant is N-(trichloromethylthio)-4-cyclohexene-1,2-dicarboximide,

5 6 11. The composition defined by claim 4 wherein the 2,530,770 Hopperstead Nov. 21, 1950 toxicant is chlordane. 2,731,338 Fike et a1. Jan. 17, 1956 References Cited in the file of this patent ()THER REFERENCES UNITED STATES PATENTS 5 Roark: U.S.D.A., A Digest on Infor. on Chlordane, 1,881,745 Linder Oct. 11, 1932 publ. E-817 (1951), p. 10. 2,163,720 Vaughn June 27, 1939 Frear: Chem. of Insecticides, Fungicides and Herbi- 2,509,233 Kaberg May 30, 1950 cides, 2nd ed., 1948, p. 67. 

1. THE WETTING AND DISPERSING AGENT COMPRISING 30 TO 80 PERCENT BY WEIGHT OF CONDENSATION PRODUCT OF ONE MOLE OF ROSIN ACID AND FROM 5 TO 20 MOLES OF ETHYLENE OXIDE, FROM 10 TO 35 PERCENT OF AN ACETYLENIC GLYCOL HAVING THE FORMULA 